The results of the studies of changes in biological and enzymatic activity of soils depending on the anthropogenic influence and the size of soil aggregates are presented. The work was carried out in 2015-2021 in the conditions of the south-east of the Central Chernozem region. The soil of the experimental site is ordinary (segregational) medium–sized medium-humus heavy loamy chernozem. The objects of research are long–used arable land and the layland used for haying since 1882. The quantitative change of individual groups of microorganisms, determined by the nature of the impact on the soil cover, is shown. The total number of microorganisms in both arable land and chernozems under natural vegetation was at the same level of 40.0 and 39.3 million CFU, respectively. Significant differences in the biological activity of chernozems by individual groups of microbial cenosis structure were noted. An increase in the number of ammonification bacteria on the arable analogue was revealed by an average of 30.7%; micromycetes by 4.4%; cellulolytics by 46.4%; nitrifiers by 46.9%; calculated humification coefficient by 45.4%. According to other components of microbial cenosis, the advantage of layland steppe soils is noted: actinomycetes by 18.5%; humus mineralizers by 11.8%. An increase in the activity of most groups of microorganisms was shown in the smaller structural units of 1-5 mm. In larger mesoaggregates, CFU numbers tend to decrease. This pattern is most clearly traced in agrogenically altered soils. In the soils occupied by natural vegetation, there is a higher activity of biochemical processes.

The eff of herbicides (Bison, Stratos Ultra) and the preparations of natural origin (Bio-Fish, BioAlgo) on the yield formation, sowing qualities and initial growth of the mid-ripening soybean variety Zhuravushka selected by the Federal Scientifi Center "All-Russian Scientifi Research Institute of Soybean" was studied. The studies were conducted in 2020 and 2021 in the experimental fi of the All-Russian Scientifi Research Institute of Soybean located in the southern part of the Amur Region (Sadovoye village, Tambovsky District). It was found that an average of two years of application of the preparations of natural origin Bio-Fish and Bio-Algo for pre-sowing treatment of seeds and vegetative plants increased the safety of the plants to the harvest period and crop yield, as well as improved the seed quality. The greatest preservation to harvesting was observed when the seeds were treated before sowing with Bio-Fish and the vegetative plants with herbicides (93.9%, which is 6.4% more than in the control variant and 7.8% more than in the variant where only herbicide treatment was used). Analysis of the yield structure showed that, on average over the years of research, pre-treatment of seeds with Bio-Fish and the vegetative plants with herbicides Bison, Stratos Ultra increased the number of beans to 5.8 pieces, and the seeds to 12.9 pieces per plant compared to the control variant. Seed weight per plant increased to 2.47 g relative to the control. The use of biological preparations increased the biological yield regardless of the treatment variant by 0.64 t/ha compared to the control and by 0.66 t/ha compared to the herbicide treatment.

The results of the evaluation of the genetic collection of black currants on the multiple racemes trait for increasing the productivity of the crop in the conditions of the Bryansk region are presented. The index of the number of racemes with fruiting on one shoot node was studied. It has been shown that under the conditions of the southwestern part of the nonchernozem belt of Russia (Bryansk region), formation of one generative bud in the axils of leaves is typical for the crop, but there are forms in which some nodes are capable of forming 2-3 racemes with fructification. It has been found that out of 132 varieties of the genetic collection studied, 116 specimens (87.9%) formed nodes with 1-2 generative buds. As a result of the studies, varieties with 3-4 inflorescences on the nodes capable of bearing fruit were selected (Dar Smolyaninova, Debryansk, Bryansky Agat, Selechenskaya 2, Ladushka, Orlovsky Vals, Istok, Chudnoe Mgnovenie, Yubileinaya Kopanya, Vera, Chernavka, etc.). Their use in further crosses will produce more productive genotypes. The most productive combinations of the crosses have been identified according to the yield of progeny forming 2-4 generative formations on one node (63-35-1 × Litvinovskaya, Svityazyanka × Selechenskaya 2, Debryansk × Dar Smolyaninova, Chudnoe Mgnovenie × Golubichka, 10-141-2 × Partizanka Bryanskaya, Debryansk × Litvinovskaya). Promising selected forms (3-63-01, 5-82-02, 8-69-01, 5-45-02, 4-18-01, 4-94-1, 4-18-02, 2-30-01, etc.), which combine the multiple racemes feature with other economically valuable indicators (resistance to pathogens, large fruits, dessert taste of fruits, number of berries in the raceme, their one-dimensionality) are highlighted.

The results of the study of 30 flax samples of different ecological and geographical origin from the collection of the N.I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR) are presented. The varieties of the Russian selection 14, Chinese 6, Ukrainian 5, French 4, Belarusian 1 have been investigated. The influence of genotypes and weather conditions on the manifestation of economic traits by multivariate analysis of variance has been established. Field studies were conducted in the sub taiga zone of the Tomsk region in 2015-2017. Natural and climatic conditions met the requirements for the cultivation of fiber flax. By total and technical stem length the best varieties of the Chinese selection Heiya 4 (K-8485), Sxy 7 (K-8689), the Russian hybrid Tomsk 16 * Success (K-8544), the French variety Drakkar (K-8493), the Ukrainian Glazur (K-8695), 66-72 and 60-66 cm respectively, were significantly higher than the standard Tomsk 16. According to the fiber content in the technical part of the stems (38-40%) the following varieties were the leaders: the Russian selection P-3989 (K-8672), A-236 (K-8692), M-249 (K-8693), the French selection Alizee (K-8494), Agatha (K-8492), Melina (K-8495), and the Ukrainian selection Vruchy (K-8694), were significantly above the Tomsk 16 standard. By the fiber mass (91-104 mg) the French varieties Drakkar (K-8493) and Alizee (K-8494), the Ukrainian varieties Vruchii (K-8694) and Glazur (K8695), the Russian varieties A-236 (K-8692) and M-249 (K-8693) reliably exceeded the Tomsk 16 standard by 6-44 mg. The flax varieties of the Russian selection P-3989 (K-8672), Dobrynya (K8504), A-236 (K-8692), the Chinese Heiya 4 (K-8485), Heiya 13 (K-8486), Tyy 13 (K-8687), the French Agatha (K-8492), Drakkar (K-8493), Alizee (K-8494), Melina (K-8495), and the Ukrainian Gladiator (K-8505) and Vruchiy (K-8694) were recognized as promising and were included in the breeding process as male seed parents. The resulting hybrid material has been on trial in the selection nursery from 2017 and the second year of breeding from 2021.

The results of the study of starch content in corn hybrid combinations are presented. As a result of the study of experimental hybrids created on the basis of VIR collection material, the breeding and combinational value of the lines in terms of grain content and starch yield per 1 ha was revealed. The results of starch harvesting per unit area are given. The experiment includes simple hybrids (30 combinations) obtained using the full top-cross crossing scheme. In the study, the RCK 7, B 293 lines and the synthetic population of RNIISK 1 were used as testers. The interval of variation of starch content in the grain during the study period varied from low values to the average indicator. It was 60.9% to 65.2% in 2020, and 59.3% to 66.1% in 2021. The lines with high effect of total combining ability by starch content in the grain (X 46, Bz 6, Om 12, UV 106), and hybrid combinations of UV 25 / PCK 7 (63, 3-64.2%), KC 75 / PCK 7 (62.7-64.4), HLG 948 / PCK 7 (63.5-64.1), Kin 073 / PCK 7 (63.4-63.8), UV 106 / PCK 7 (63.6-66, 1), KC 25 / B 293 (63.0-63.5), HLG 182 / B 293 (63.5-63.6), KC 75 / B 293 (63.1-63.5), HLG 182 / RNISK 1 (62.9-63.6%) were identified. The experimental hybrids that form the highest yield of starch per unit area were identified: HLG 182 / RCK 7 (3,12-3,58 t/ha), UV 106 / RSK 7 (2,77-3,11), X 46 / B 293 (3,22-3,39), Om 12 / B 293 (2,72-3,85 t/ha).

The results of the study of the stranger American species Galinsogaparviflora and G. guadriradiata in the south of the Primorsky Territory (Russia) are presented. Field studies were conducted in 20182022 on the territory of the Primorsky Territory in urban and rural settlements, in specially protected natural areas (V.L. Komarov Ussurisky Nature Reserve). Literary data, information from Internet resources, herbarium specimens have been analyzed. Studies have found that over the past 30 years, the invasive range of species of the genus Galinsoga in the south of the Far East has increased significantly. At present, in the Primorsky Territory, these adventive species actively disperse over anthropogenically transformed territories (roadsides, abandoned fields and meadows, city parks and squares, adjacent territories, construction pits, etc.) and are noted in most administrative-territorial districts of the region. Galinsoga species have a sporadic distribution in the northern and eastern parts of the region. G. guadriradiata and G. parviflora grow en masse in the areas with developed agriculture (western and central Primorsky Territory). In Vladivostok, several large herbaceous communities are noted with dominance of G. guadriradiata, up to 100 m² in area with projective coverage of 90-100%. The penetration of species of the genus Galinsoga into specially protected natural areas is of great concern. Therefore, further monitoring of the invasive range of these species in the south of the Russian Far East is necessary.

The climatic conditions of the Republic of Bashkortostan require the creation of varieties with high resistance to a complex of biotic and abiotic stressors of the region of cultivation. The data on economically valuable characteristics of a new variety of black currant Belskaya (breeding number 4-46) are presented. The black currant variety Belskaya was bred in the Republic of Bashkortostan in 1997 from pollination of the Valovaya (Krupnaya × Bredtorp × Khludovskaya) and Karaidel (Pamyati Michurina × Compactnaya). The year of sowing is 1998, the beginning of fruiting is 2002, the selection of an elite seedling is 2003, the transfer to the state varietal testing is 2013. The primary study of varietal samples was started in 2005 according to the planting scheme of 3 × 1 m. The control variety was Valovaya which is widespread and zoned across all regions of the Russian Federation. The Belskaya variety is characterized by high winter hardiness. There were no signs of freezing in severe winters, in the control variety Valovaya damage was noted up to 1 point with freezing of the tops of the annual growth. The leaf apparatus of the variety is resistant to sunburns. During the hot and dry summers (2010, 2011), it was distinguished by high drought resistance, while its productivity was higher than the control variety. The new variety is characterized by high productivity (yield on average 12.7 t / ha), and is resistant to shedding. It has fi resistance to American powdery mildew, weakly affected by anthracnose. Berries are one-dimensional, black, round‒oval shape, weighing 2.3 g (maximum 2.6 g), sweet and sour delicate taste. The maturation period is average. In 2022, the Belskaya variety was included in the State Register of Breeding Achievements of the Russian Federation in the Ural region.

An outbreak of infection caused by Pestivirus H (virus of bovine viral diarrhea – mucosal disease of the third kind, BVDV-3) in a dairy farm with high morbidity and mortality in animals of different ages is described. In some sick animals a full complex of pronounced symptoms characteristic of "classical" bovine mucosal disease was registered: erosions and ulcers on the nasal mirror and tongue, foaming from the mouth, serous discharge from the nose, hemorrhagic inflammation and pronounced longitudinal erosions on the mucosa of the esophagus, rennet stomach and intestine. Cows miscarried at different stages of pregnancy. The coefficient of effective insemination decreased to 20%. The course of the disease was complicated by the involvement of the bovine herpes virus type 4, bacteria of the family Pasteurellaceae and Clostridium spp. in the infectious process. The BVDV-3 genome was found in a wide range of internal organs of aborted fetuses, calves, and adult animals. According to sequencing data, the pathogen was classified as subtype 3a. Phylogenetic analysis of the 5'-untranslated region of the virus genome (5'-UTR) showed its close relationship to the strains isolated in Italy and Brazil, most of which were previously identified as contaminants of fetal bovine serum and live vaccines against viral infections of cattle. No specific prophylaxis against BVDV-3 infection has been developed at this time, therefore, it is necessary to update and improve diagnostic methods, optimize control measures to prevent the spread of virulent strains of the pathogen, and control the safety of the vaccines used.

The results of determining the most effective model for predicting the level of manganese in the muscle tissue of Hereford cattle for in vivo assessment of the elemental status of animals by low invasive methods are presented. The experiment was carried out using hematological and biochemical blood tests and atomic absorption analysis of the muscle tissue of cattle. The data obtained are used to fit the regression model using the least square method. Skeletal muscle samples weighing 100 g from the diaphragm muscle of the Hereford cattle bred in the southern part of Western Siberia in the conditions of industrial complex were taken for analysis. Manganese concentration in tissues was assessed by atomic absorption analysis on an MGA-1000 spectrometer. The content of erythrocytes, leukocytes, and hemoglobin was determined on an automatic hematology analyzer PCE-90VET. Protein, albumin, globulin, urea, uric acid, and cholesterol levels were determined by photometric methods on a Photometer-5010 semi-automatic biochemical analyzer. The effects of regression models were calculated using the least square method. Selection of the best model for efficiency and accuracy of model estimation was based on a comprehensive assessment of the values of internal and external quality criteria. Statistically significant associations (p < 0.05) were found between the dependent and independent variables. Within the pool of predictors, correlation (p < 0.05) was observed. As a result of model fitting, an optimal regression equation including two indicators (erythrocyte sedimentation rate and globulin level) for predicting manganese levels in bovine muscle tissue was obtained. There are no signs of multicollinearity between the main effects of the model, which confirms the values of the variance inflation factor 1.2. The resulting model satisfies the necessary assumptions about the residuals. The distributions of the model residuals fall within the confidence intervals of the normal distribution curve. The autocorrelation coefficient was 0.039 (p > 0.05), indicating the independence of the residuals. The resulting model can be used for in vivo assessment of manganese concentration in bovine muscle tissue.

Mitochondrial DNA polymorphism, which is one of the most common genetic markers, is actively used in the study of various animal species. Since the mitochondrial genome has evolved over many years within a species, this has influenced the fixation of mutations and the formation of mitochondrial lineages that share a common origin and form mitochondrial genomes, called mtDNA haplogroups. The objectives of the work were to evaluate the genetic diversity of pigs of two maternal breeds of domestic reproduction based on the analysis of mtDNA D-loop polymorphism and to compare the results obtained with identical sequences from the NCBI database by breed and their geographic distribution. 39 Landrace pigs and 49 Large White pigs were used for the study. MtDNA was isolated from tissue samples (ear notch). The number of haplotypes, haplotypic and nucleotide diversity, and the average number of nucleotide substitutions per site were determined to assess the genetic diversity. 23 polymorphic sites were found: 21 in Landrace pigs, 17 in Large White pigs. A total of ten haplotypes were identified in the study population. The NCBI database found 75 identical sequences for pigs of different breeds bred around the world. After determining the nucleotide sequences of the D-loop fragment of the mtDNA of Landrace and Large White pigs of domestic reproduction and comparing them with the sequences from the NCBI database, the presence of identical sequences in the animals we studied and in the representatives of European and Asian breeds, including commercial and local was established. The materials obtained show that the assessment of mtDNA polymorphism contributes to the identification of phylogenetic relationships between populations, tracing of pedigree processes, and can be considered as an additional criterion of selection and breeding work.

The problem of studying the degree of influence of the index "Period of productive life/productive longevity" of the servicing bulls on the duration of productive use of their progeny is not sufficiently covered in the scientific literature, which substantiates the relevance of the research. A comparative assessment of economically useful features of the daughters of servicing bulls with the index value from 103 to 117 has been carried out. Dynamics of the experimental animals' mortality is determined in the period from birth to the end of the second lactation, the level of milk productivity according to the data for the first and second lactations. It was found that mortality among the daughters of the servicing bulls with an index equal to 103 and 105 was the highest in all physiological periods and amounted to 80.0 and 78.1% at the end of the experiment, respectively. In the groups of the daughters of the servicing bulls with index values of 109 and 117, the proportion of animals that died out reached 62.9 and 65.6%. The lowest productivity for the first and second lactations was recorded in the daughters of the servicing bull with the index value of 103 6760.2 and 7100.7 kg of milk. The daughters of the servicing bull with the index equal to 117 were distinguished by the highest milk productivity 7475.9 and 8158.3 kg of milk in two lactations. Analysis of the obtained data shows that fixation of servicing bulls to the breeding herd taking into account the "Period of productive life/productive longevity" index will make it possible to obtain more robust progeny with good productive qualities.

The research was conducted in the laboratory of molecular genetic expertise in 2018 and 2019 within the framework of the state assignment on the topic "Development of genetic-selection and theoretical foundations for the conservation and effective use of the gene pool of cattle in the Ural region with the use of modern biotechnologies". The object of the study is the cattle of Holsteinized black-and-white breed. The main task is to analyze the degree of influence of the somatotropin (GH) gene polymorphism on lactation performance indicators. In the course of the study, DNA from 270 cows was isolated, the polymorphism of the somatotropin gene was determined based on the obtained data, and the relationship between different genotypes and indicators of live weight, milk yield, protein mass fraction and fat mass fraction in milk was established. The results were biometrically processed using IBM SPSS Statistics 23 software program. It was revealed that LL is the main genotype of the GH gene among the representatives of the Holsteinized black-and-white breed (frequency of occurrence 77.0%). The proportion of LV and VV genotypes in the population is 21.9 and 1.1%, respectively. During the observation period, cows carrying the LL genotype showed higher milk yields in the first and third lactations. The difference with their peers was 202-2334 kg (p ≤ 0.05). A tendency towards increased protein content in milk was recorded in animals with the VV genotype. In the first lactation, the difference with LL and LV genotype carriers was 0.03 and 0.06%, respectively. In the third lactation, individuals with the VV genotype surpassed their female counterparts in protein content by 0.07 and 0.12%, respectively.

The process of snow cover formation on the fields with different surface conditions was studied. The research was conducted in the spring of 2022 in the steppe farming zone of the Omsk region. The effect of high plant stand of cereal crops remaining after harvesting by standing crop stripping on the amount of snow cover and the volume of spring moisture accumulation in the soil as a reserve for increasing the yield in the steppe regions of Western Siberia is considered. The results of determining the height of snow cover on a fallow field (complete fallow), on fields under grain crops harvested by different methods: with a direct harvester followed by flat tillage; with a direct harvester without subsequent tillage; with a combing harvester at the height of the stem during harvesting up to 0.55 m are presented. In the course of the study it was found that during harvesting by the stripping method, the moisture reserves in the snow cover were 2.2 times higher compared to the stubble background, 3.7 times higher compared to the stubble background treated with a flat cutter, and 4.1 times higher compared to the fallow field (control). Based on the data obtained, the conclusion is made about the possibility of using this method to form the conditions for moisture accumulation in the arid steppe zone without additional measures for snow retention, which should have a positive impact not only on the yield of cultivated crops, but also on the agro-economic indicators.